某些因素对玻璃苗形成的影响和玻璃苗在形态解剖上的特点

瑞香试管苗的玻璃化受到细胞分裂素浓度和茎尖外植体大小的影响,细胞分裂素浓度越高,茎尖外植体越小,产生的玻璃苗越多。玻璃苗与正常试管苗的茎尖在形态结构上有明明显差别,主要表现为顶端分生组织原体原套结构异常和细胞的明显液泡化。     

诱导突变高粱愈伤组织初探

本实验以突变体高粱的不同外植体 ,成熟种子、成熟胚、茎尖、和幼胚等为材料 ,诱导愈伤组织。经出愈率和生长状况观察 ,幼胚最好 ,成熟胚较好 ,成熟种子和茎尖略差。对于茎尖 ,2 ,4 D与KT搭配较好 ;成熟胚而言 ,不加细胞分裂素 ,加适量 2 ,4 D浓度效果较好 ,幼胚愈伤组织诱导和培养不需要细胞分裂素 ,加浓度为 2 .0mg/L2 ,4 D效果较好 ;若加KT ,同时要提高 2 ,4 D浓度 ;成熟种子培养 ,需要细胞分裂素     

苹果组织培养中的玻璃苗问题（简报）

苹果茎尖接种在NH_4~+和NO_3~-浓度比不同的培养基上,第二代均出现玻璃苗。在浓度比较低的培养基上,绿茎的玻璃苗率和病情指数较小,浓度比高的培养基上发生的玻璃苗转接到较低比值的培养基上后,玻璃苗症状减轻,并有少量转为正常苗。一定范围内降低培养基中氨态氮的比例利于防止或减轻玻璃苗发生。     

红根草的组织培养与快速繁殖研究

研究了红根草不同采集季节、外植体类型与消毒效果,不同激素浓度和激素组合与芽及根的诱导,及试管苗的移栽。结果表明,不同外植体类型消毒效果为茎节>茎尖>植株抽茎前的生长点;4~6月份采样最佳;MS+BA0.8~1.6mg/L+NAA0.2mg/L、MS+BA0.2mg/L+NAA0.02mg/L、MS+NAA1.0mg/L分别用于初代、继代、生根培养效果最好;试管苗移栽成活率达90%。     

麝香石竹玻璃苗与正常苗的生理特性差异

诱导麝香石竹茎段外植体产生不定芽的分化,所得到的正常苗与玻璃苗的生理特性明显有差异。表现在玻璃苗的鲜重、干重、粗纤维和叶绿素含量与正常苗相比显著降低;玻璃苗的可溶性糖含量增加38％,而蔗糖含量下降63%,束缚水含量显著增高,自由水含量明显降低;玻璃苗的淀粉酶总活性也明显升高,碱性和中性区过氧化物酶同工酶活性显著提高而酸性区的同工酶活性有所下降。然而,玻璃苗和正常苗形成时的芽分化频率以及伸长生长量之间无明显区别。结果表明,麝香石竹试管苗的玻璃化可能是在碳水化合物代谢、氮代谢和水分存在状况等发生生理异常的情况下在芽分化启动后的生长过程中发生的,而不是在芽分化启动时已经决定的。     

不同培养条件对薄荷试管苗玻璃化现象的影响

以江苏东台产薄荷(M entha haplocalyxB riq.)的茎尖为外植体,以MS为基本培养基,研究了培养基添加物和培养条件对薄荷试管苗玻璃化现象的影响。结果显示,导致薄荷玻璃化苗产生的主要因素是培养基中的6-BA、蔗糖和琼脂浓度以及培养温度和光照时间;当6-BA浓度为2 mg.L-1、蔗糖浓度为4%、琼脂浓度为0.70%、培养温度25℃、光照12 h.d-1(2 000 lx)时,薄荷试管苗的繁殖系数较高,玻璃化苗率较低。     

茎椰菜试管苗繁殖的初步研究

茎椰菜(Brassia oleracea var.italica)是国际市场上畅销的高级蔬菜。目前,上海地区生产用种都是从国外进口的F_1种子,不能留种应用。在培育我国自己的品种中,为了利用组织培养技术来加快自交系、自交不亲和系的繁殖和进行春季单株留种,同时对大量繁殖F_1试管苗的方法作些探索,进行了茎椰菜试管苗繁殖的初步研究,探索了生长素和细胞分裂素种类、浓度和配比对花器官的愈伤组织分化的影响及加速试管苗繁殖的方法。     

杭白菊茎尖组织培养及试管苗繁殖技术研究

采用茎尖组织培养技术,建立了杭白菊中大洋菊(Chrysanthemum morifolium Ramat.)的无菌试管苗体系.通过基本培养基和激素配比实验,筛选出杭白菊试管苗快速繁殖的最佳培养基组成.结果表明:最适宜的外植体为直径0.3 mm的茎尖;诱导丛生芽的最适培养基为:MS 6-BA 0.1 mg*L-1 IAA 0.02 mg*L-1;诱导试管苗生根的最适培养基为:1/2MS IAA 0.7 mg*L-1.用电子显微镜进行病毒检测后,筛选出2个脱病毒株系,脱病毒试管苗可作为今后提供优质种苗的种源.     

THIDIAZURON的细胞分裂素活性研究——Ⅰ.对番木瓜(Carica pentagona)愈伤组织诱导及芽生长的作用

以番木瓜(C.Pentagona)为材料,研究了thidiazuton(TDZ)的细胞分裂素活性。用Litz改良的MS为基本培养基,附加TDZ浓度为:0、0.002、0.02、0.2、2.0mg/l,与NAA0.2mg/l结合使用(NT)或否(T),并以附加0.2mg/l NAA和2.0mg/l普通细胞分裂素如2ip,玉米素、BAP等之一(NP等)的培养基为对照,培养番木瓜试管繁殖幼苗的茎外植体。结果表明,节和节间外植体在NT和T上的愈伤组织诱导及节上休眠腋芽生长的反应明显不同。与普通细胞分裂素相比较,TDZ的活性较2iP等高出百倍乃至千倍以上,而且与普通细胞分裂素相同,TDZ可以与外源或内源的生长素发生协同作用。对以上结果进行了讨论。     

影响枣试管苗生长分化的因素（简报）

骏枣试管苗在生长与分化过程中,以ＭＳ培养基的营养水平,温度２５￣２７℃为适宜,外植体是茎段比茎端好,斜剪和斜插对生长分化有利,生长素为０．３￣０．５ｍｇ／Ｌ为宜,细胞分裂素（６－ＢＡ）以１￣１．５ｍｇ／Ｌ为宜,两者最佳配比为１：３。     

葡萄试管苗热处理结合茎尖培养脱病毒效果的研究

对７个生食葡萄品种的试管苗热处理结合茎尖剥离培养脱除病毒的方法做了研究,结果表明,从热处理试管苗剥离的茎尖培养成活率为６１．２％,其中有１８．１％的成苗。各品种热处理试管苗剥离的茎尖分化再生能力不同：先形成愈伤组织的成苗率较低,而先分化芽的茎尖成苗率较高。这一方法对扇叶病毒和卷叶病毒的脱除率达９２％以上。     

金花茶子叶在离体培养中胚状体的发生和小植株的形成

研究了金花茶(Camellia chrysantha(Hu)Tuyama)子叶在离体培养中体细胞胚状体发生的条件。在MS基本培养基中附加苄基嘌呤(BA)或苄基嘌呤与萘乙酸(NAA)组合,诱导了胚状体发生。组织学观察表明,胚状体起源于子叶的表皮细胞。在增添细胞分裂素和生长素的MS或改良B_5液体培养基里振荡培养,明显地促进了胚状体根的生长和茎的发育。胚状体在继代培养中能保持旺盛的再生能力。已得到两个繁殖率较高的胚状体无性系。在合适的条件下,胚状体能长成正常的小植株。     

PLANTLETS FROM PETAL SEGMENTS,PETAL EPIDERMIS,AND SHOOT TIPS OF THE PERICLINAL CHIMERA,CHRYSANTHEMUM MORIFOLIUM ‘INDIANAPOLIS'

Cultivated chrysanthemums, especially the greenhouse series of ‘Indianapolis’ cultivars, are probably periclinal chimeras for flower color. Therefore, in vitro propagation of chrysanthemum, which has recently been described, might produce plants not true to type. To test this, plantlets were generated from cultures of petal segments, petal epidermis, and shoot tips; these plantlets were grown to flowering to determine whether chrysanthemums with two genetically different chimeral layers in the petals are stable in tissue culture. Layer I displaced layer II in the formation of new meristematic areas in shoot tip and petal culture, showing that such chimeras are unstable in culture. Many more abnormal morphological types were exhibited by the plants which were regenerated from petal cultures rather than those from shoot tip cultures. Abnormalities included quilled and incised petal forms, as well as lack of anthocyanin pigmentation, characteristics which may not be attributable to the rearrangement of chimeral layers. Paramutation, true mutation, and environmenal effects are offered as possible explanations for this phenomenon.     

CYTOKININ-GIBBERELLIN REGULATION OF SHOOT DEVELOPMENT AND LEAF FORM IN TOBACCO PLANTLETS

Callus and plantlets derived from callus cultures of Nicotiana tabacum var. Wisc. #38 were grown on medium containing serial combinations of gibberellic acid (GA₃) and the cytokinin 6-(3-methyl-2-butenylamino)purine (2iP). Increasing levels of both growth substances resulted in the production of greater amounts of both callus and shoot tissue. More buds were induced when the cytokinin level was increased, and this effect was counteracted by raising the GA₃/2iP ratio. Furthermore, the size and form of the shoots depended on the GA₃/2iP ratio. High ratios resulted in tall, spindly plants with narrow leaves while low ratios resulted in short shoots with rounded leaves.     

棉花组织培养中异常苗的发生与转化

研究了棉花 (Gossypium hirsutum L.)组织培养中异常苗发生的类型、规律、影响因素及转化为正常苗的途径及技术。结果表明 ,在棉花组织培养中异常苗发生的频率极高 ,且形式多样 ,大体可分为生长点异常苗、叶片异常苗、胚轴异常苗、联体苗、丛生叶苗、单叶苗、玻璃化苗、白化苗、褐化苗和重新愈伤化苗等 1 0类。其中生长点异常苗和叶片异常苗最为常见。影响异常苗形成的因素很多 ,其中主要有外植体种类、培养基组成、培养方式和培养时间。有的异常苗来源于畸形胚 ,有的异常苗由正常苗转化而来。在合适的条件下异常苗可转化为正常苗 ,但不同培养基对异常苗转化为正常苗的影响不同 ,且不同基因型的异常苗转化为正常苗的能力也有差别。此外 ,从外界调控机制与棉花培养细胞的内在发育机制的相互作用方面讨论了造成棉花组织培养异常苗发生的原因 ;并讨论了降低异常苗产生频率的技术途径和异常苗存在对棉花组织培养的影响     

In vitro propagation and the acclimatization effect on the synthesis of 2-hydroxy-4-methoxy benzaldehyde in Decalepis hamiltonii Wight and Arn.

The present study reports a high frequency in vitro propagation protocol through apical bud sprouting and basal organogenic nodule formation in shoot tip explants of Decalepis hamiltonii, an endemic and endangered medicinal liana. Among different combinations of plant growth regulators (PGRs) and growth additives, maximum of 8.20 shoots per explant with mean shoot length of 6.54 cm were induced on Murashige and Skoog’s medium (MS) supplemented with 5.0 µM 6-benzyladenine (BA) + 0.5 µM indole-3-acetic acid (IAA) + 30.0 µM adenine sulphate (ADS) through apical bud sprouting. On single cytokinin treatment explants did not exhibit good multiplication but showed nodulation (N₁) from the basal cut end similar to cytokinin–auxin combination (N₂). Between two types of nodular tissues, N₂ was proved to be better for maximum shoot regeneration (15.40 shoots per explant) and shoot length (4.56 cm) when cultured on MS medium supplemented with 5.0 µM BA, 0.5 µM IAA, 30.0 µM ADS and 1.0 µM gibberellic acid (GA₃). Microshoots were efficiently rooted on half-strength MS medium supplemented with 2.5 μM α-naphthalene acetic acid (NAA). After successful acclimatization in Soilrite, 95.10 % plantlets were survived in field conditions. Histological investigation proved useful in ascertaining the callogenic nature of the regenerating nodular tissue formed at the basal cut end of shoot tip explant. Acclimatized plantlets were studied for the estimation of chlorophyll and carotenoid content as well as the net photosynthetic rate (PN) during subsequent days of transfer to ex vitro condition. Moreover, acclimatization had a significant effect on biomass production and the synthesis of 2-hydroxy-4-methoxy benzaldehyde (2HMB). Maximum fresh weight (3.78 gm/plant), dry weight (0.39 gm/plant) of roots and 2HMB content (15.94 µg/ml of extract) were noticed after 8 weeks of acclimatization.     

魔芋属植物愈伤组织的诱导和再生植株的研究

用云南魔芋(Amorphophallus yunnanensis)、白魔芋(A.albus)、花魔芋(A.revieri)和勐海魔芋(A.bannaensis)等四个种的叶、鳞叶、花序、匍匐茎、块茎和茎尖为外植体,诱导产生小植物。可通过三种途径获得魔芋再生植株:(1)由外植体诱导愈伤组织,再分化小植株:在添加0.5—1.0mg/1 NAA和BA或KT、ZT的MS培养基上,高频率地诱导瘤状愈伤组织形成,发现NAA对愈伤组织的诱导是必不可少的,而细胞分裂素与之组合,促进瘤状愈伤组织的形成和发育,在无激素或低浓度激素的培养基上,瘤状愈伤组织分化出小植物;(2)茎尖和鳞叶、块茎切块培养,诱导形成多芽苗,产生再生植株;(3)块茎切块诱导产生微型小块茎,然后分化芽和根,长成小植物。本研究为魔芋的快速繁殖提供了新的手段。     

In vitro propagation of emetic nut Randia dumetorum (Lamb.)

An efficient protocol for in vitro shoot multiplication of Randia dumetorum (Emetic nut) has been developed. The seeds of R. dumetorum were germinated in vitro in MS medium in 5 weeks. Subsequent propagation using shoot tip as an explant was carried out in MS medium along with different concentrations and combinations of BAP (0.5-2.0) and NAA (0.0-2.0). Maximum shoot multiplication was obtained (12.7 shoots per shoot tip) in MS medium containing 1 mg/L BAP and 1 mg/L NAA. Micropropagated shoots were rooted in 1/2 MS medium supplemented with 1 mg/l IBA. This is the first report of in vitro plant propagation of R. dumetorum. In vitro grown plantlets showed a survival rate of 70% after 2 months of transplantation to natural environment.     

The apical control of lateral bud development in excised shoot tips of Cuscuta reflexa cultured in vitro

Excised shoot tips of Cuscuta reflexa Roxb. (dodder), a rootless and leafless angiospermic plant parasite, were cultured in vitro for the study of the control of lateral bud development by the apex. In a chemically defined medium lacking hormones, the basal bud alone developed into a shoot. The addition of coconut milk to the growth medium induced the activation of multiple lateral buds, but only a single bud developed further into a shoot. The decapitation of this shoot induced the development of another shoot and the process could be repeated. This showed the controlling effect of the apex in correlative control of bud development. Application of indole-3-acetic acid to the shoot tip explant delayed the development of the lateral bud. Gibberellic acid A₃ induced a marked elongation growth of the explant and reinforced apical dominance. The direct application of cytokinin to an inhibited bud relieved it from apical dominance. A basipetally decreasing concentration gradient of auxin may prevail at the nodes. Bud outgrowth is probably stimulated by cytokinin produced locally in the bud.